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Macintosh SE/30 M5119 - Restoration
Posted by: joshc on 2025-01-21 11:45:02 I was thinking that too, but removing that entire chip feels like serious business. Is the VLSI chip impossible to find an NOS replacement for? Can that be socketed? Do you have a hot air station/gun? Removal is easy with a hot air gun. I wouldn't socket it, that's just going to create another potential weak spot. The ASC is a custom Apple chip so not easy to find replacements for.
Posted by: GreenBar0n on 2025-01-21 14:31:11 Do you have a hot air station/gun? Removal is easy with a hot air gun. I wouldn't socket it, that's just going to create another potential weak spot. The ASC is a custom Apple chip so not easy to find replacements for. Thanks! I do have the standard Yihua 959D. But UE10 is surrounded by those new tantalum caps. I do have kapton tape and foil. If I'm going to remove UE10, I really need better magnification, and it doesn't come cheap. Might have to wait until I can fix that.
Posted by: GreenBar0n on 2025-01-21 17:13:20 Instead of going with a desk mounted AmPro for $600+, I'm trying a $139 Amazon one, it should be here in the next couple of hours, with same day delivery. https://www.amazon.com/Andonstar-AD246S-M-Microscope-Biological-Compatible/dp/B09VPPS96M
Posted by: GreenBar0n on 2025-01-22 11:48:55 Got the new scope, might take some getting used to, there's a disconnect between the eyes and hands having the screen remote - just feels weird at the moment. Looks incredible though, now that I can see what I'm doing. Will practice getting my hands and eyes to agree on this, and then remove the VLSI chip - without ruining any traces, hopefully.
Posted by: GreenBar0n on 2025-01-22 12:58:16 Taped off UE10. Working up the courage to do this, now that things are in order.
Posted by: GreenBar0n on 2025-01-22 15:12:44 As soon as the hot air flowed, the kapton tape lifted, and then the foil got in the way. Removed the kapton tape and foil, used the square nozzle for the hot air, flooded UE10 with flux, and set the Yihua 959D to 400°C, with a fan speed of 7. Took about 2 minutes and kept bumping it with tweezers, until it loosened and came off. The microscope didn't help with using the hot air, it gets in the way directly above it. But it does help, and I will be keeping it. Has video capture too. There are three pads that will need to be fixed, or bodged. We'll see what repairing this achieves in relation to the symptoms: no chime, simasimac.
Posted by: GreenBar0n on 2025-01-22 15:25:48 The three missing pins are 19, 20, and 35. Pin 35 is Vcc for UE10, and it was rotted off like UE8 was. Need to manage my expectations, but this feels like I'm on to something significant here.
Posted by: obsolete on 2025-01-22 15:35:35 Nice work. Based on your photo, I'm suspicious of pin 22 also.
Posted by: GreenBar0n on 2025-01-22 15:45:56 Thanks! I'm getting ready to check every pad and via connected to UE10, on both sides of the board, right now.
Posted by: croissantking on 2025-01-22 16:46:17 We'll see what repairing this achieves in relation to the symptoms: no chime, simasimac. I wager you’ll get: chimes of death, simasimac. Why? Because the SE/30 will boot without an ASC. Let’s see…
Posted by: GreenBar0n on 2025-01-22 19:48:15 Nice work. Based on your photo, I'm suspicious of pin 22 also. Pin 22 is also broken. I wager you’ll get: chimes of death, simasimac. Why? Because the SE/30 will boot without an ASC. Let’s see… This has to be done, might as well be now.
Posted by: GreenBar0n on 2025-01-22 19:52:54 Looks like TL071 and Q2 are also rotted. What's TL071 and Q2 responsible for? Looking for them on the schematic now.
Posted by: GreenBar0n on 2025-01-22 20:06:24 What's TL071 and Q2 responsible for? Looking for them on the schematic now. More sound chips. In fact the direct connection to the speaker.
Posted by: GreenBar0n on 2025-01-22 20:49:52 Looks like UD12 is corroded and may have some bad traces. UD12 is listed in the Serial and Sound schematic. Will remove TL-071, Q2, and UD12 in order to check the traces and remove the corrosion.
Posted by: croissantking on 2025-01-22 21:56:19 TL071 is an audio amplifier and 26LS30 is a serial port line driver (an electronic circuit that amplifies a signal and drives it along a transmission line or cable)
Posted by: codevonlux on 2025-01-22 23:04:28 SE/30 will not boot without ASC. I tried it on multiple boards. (simasimac) 26LS30 will not prevent a boot TL071/Q1/Q2 issue will make you unable to hear the death chime if there's one from the speaker, they are audio amplifier/driver to drive internal speaker. Line-out jack should work fine without those.
Posted by: GreenBar0n on 2025-01-23 00:40:57 TL071 is an audio amplifier and 26LS30 is a serial port line driver (an electronic circuit that amplifies a signal and drives it along a transmission line or cable) Thanks for the info, I really appreciate it! So many sound chip problems on this board. SE/30 will not boot without ASC. I tried it on multiple boards. (simasimac) 26LS30 will not prevent a boot TL071/Q1/Q2 issue will make you unable to hear the death chime if there's one from the speaker, they are audio amplifier/driver to drive internal speaker. Line-out jack should work fine without those. This is giving me hope, thank you! I've looked this board all over, and there is no other corrosion near the CPU, RAM, ROM, or muxes. It was starting to worry me that fixing the ASC wouldn't cure the simasimac, or even have a chance of doing so; really glad to hear a missing/broken ASC can and will halt a boot. I'm certain that these logic board problems were caused by the cap corrosion, the broken traces/areas of the board must be in those limited locations where the leaks occurred, which makes it easier to find the problem, visually. Having to find the problem with just a scope and meter alone, would probably not work out well for me even though I do have both, and an ancient lightweight electronics degree. Will give it another go tomorrow night. Thanks again for the info and reply guys!
Posted by: croissantking on 2025-01-23 01:11:50 SE/30 will not boot without ASC. I tried it on multiple boards. (simasimac) Not according to my own testing 😆 I had the ASC removed from a fully socketed Reloaded board last night and it booted up fine. It’s interesting that we’ve had different results on this.
Posted by: Arbee on 2025-01-23 18:58:29 The boot chime does wait forever on certain status bits from the ASC so it can work "by accident" due to stray bus capacitance, but I wouldn't rely on it.
Posted by: GreenBar0n on 2025-01-25 15:06:04 Got UD12 removed. Was able to scrape the board traces, and solder the broken traces closed again, no bodge wire necessary. Will go over the bare traces with UV solder mask before installing the chip again. Will have to run wires for the broken traces on UE10 pin 19, 20, and 22, like I did with Pin 35, the trace gap is too large to fix these with solder only.
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